radeonsi/ci: run a fraction of glcts-vangogh in pre-merge

Now that ACO has become the default on pre-RDNA GPUs, all pre-merge CI
coverage of radeonsi+LLVM has disapeared. Let's fix this by making
our post-merge glcts-vangogh-valve job run inpre-merge pipelines.

However, we are limited in vangogh capacity, so rather than running the
full glcts/piglit test suites we run a fraction of it to stay under 15
minutes of execution time on a single Steam Deck.

Suggested-by: Marek Olšák <maraeo@gmail.com>
Signed-off-by: Martin Roukala (né Peres) <martin.roukala@mupuf.org>
Reviewed-by: Marek Olšák <marek.olsak@amd.com>
Reviewed-by: Valentine Burley <valentine.burley@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/32865>

src/amd/ci/gitlab-ci.yml

@@ -278,17 +278,29 @@ vkcts-vangogh-valve:
     GPU_VERSION: radv-vangogh-aco
     RADV_PERFTEST: transfer_queue
 
-glcts-vangogh-valve:
+.glcts-vangogh-valve-common:
   extends:
     - .b2c-x86_64-test-gl
     - .b2c-deqp-test
     - .vangogh-test-valve
-    - .radeonsi-valve-manual-rules
-  timeout: 60m
   variables:
     GPU_VERSION: radeonsi-vangogh
     DEQP_SUITE: radeonsi-vangogh
 
+glcts-vangogh-valve:
+  extends:
+    - .glcts-vangogh-valve-common
+    - .radeonsi-valve-rules
+  timeout: 30m
+  variables:
+    DEQP_FRACTION: 4
+
+glcts-vangogh-full-valve:
+  extends:
+    - .glcts-vangogh-valve-common
+    - .radeonsi-valve-manual-rules
+  timeout: 90m
+
 vkcts-navi31-valve:
   parallel: 2
   extends: